The best free PC games

40. QWOP

Graham: QWOP is named after the keys you use to control it: QW to pump your sprinter's thighs, OP to arc his calves. The experience is what I imagine it's like to be an alien placed inside a robotic humansuit, pulling levers to manoeuvre the appendages. The result on screen is simultaneously tense and hilarious. One leg stretches out, the other hops pathetically, the runner's balance starts to slowly topple, keys are hammered in an attempt to try to return upright, and then it's over. Your score: 1.4 metres.

39. Slave of God

Graham: Increpare is better known for his puzzle games, but this neon, fuzzy, abstract club night hits you in different places by capturing the highs and lows of a night out. The dancefloor is full of spinning, elbowy forms; join them, and you might get drawn into the pull of another reveller, but you'll only ever end up alone. Head to the club's toilets, and you'll start peeing on the floor before you even reach them.

38. Companion

Graham: You're a square floating in a black void, and there are three types of objects in the environment: stars, which stick to you; cuboid objects which do nothing, and jellyfish-like creatures which move towards you and electrocute you on contact. Then, very quickly, you meet another square like you, only smaller. It's sleeping. You poke at it, and it wakes up – and hoots at you. Hello! He then follows you around, tooting curiously at the objects you find, and experimentally butting at them. Companion is a fiveminute experiment – and a successful demonstration – of how to build a relationship between a player and an NPC.

37. Robot Unicorn Attack

Graham: A stylishly camp auto-running game about a robot unicorn leaping across gaps and listening to the Erasure song 'Always' on repeat. If that doesn't make you want to play it, I definitely don't wanna be with you / or make believe with you / or live in harmony, harmony, oh love.

36. Don't Take It Personally, Babe, It Just Ain't Your Story

Phil: A visual novel in which you play a high-school teacher in the year 2027. Given access to the private messages of your class's social network, you become increasingly involved with their lives and relationships. It's a thoughtful exploration of privacy, with a surprising conclusion.

35. Facade

Tom: This one-scene interactive play casts you as sole guest at the most awkward party imaginable. Your hosts, Grace and Trip, are on the verge of marital breakup and can't help but use you to snipe at each other's flaws. A wobbly but fascinating study of social awkwardness.

34. Warsow

Phil: This cartoony FPS takes its cues from the old school. That means twitch combat and the opportunity to boast skill, speed and precision. It's movement system steals from the best – Quake and Unreal Tournament – to create an online shooter that offers both deathmatch and race servers. Master the simple but versatile control scheme and you'll be circle, strafe, wall and rocket-jumping your way past lasers, bullets and explosives. But don't let the high skill skybox put you off – Warsow is purely transitory arcade action. There's no progression or tracking, and the bots and varied modes mean that you can just jump in, jump around and get fragging.

33. Slender: The Eight Pages

Rich: Collect eight pages attached to stuff in some woods while a prick in a suit stands around and looks at you. It doesn't sound that scary, but the internet's own Slenderman is a powerfully creepy kind of eight-foot bastard. Your biggest roadblock to collecting all the pages is your own fear.

32. Hide

Chris: This indie horror game runs at a tiny resolution and is upscaled to provide a disorientating, monochrome experience. You hunt through a winter wilderness while being chased by mysterious, distant flashlights. Similar to Slender, Hide stands out through its presentation and restraint. There's no silly-looking monster to bump into, it's all atmosphere and perseverance.

31. Desktop Tower Defence

Tom: A moreish maze-building game that turns a tiny patch of desk into a warzone. Increasingly powerful creeps swarm in from the left. Slow them with ice rays, blast them with missiles and craft a long intestinal catacomb of death out of gun turrets to ensnare and destroy them.